Connector having a bypass capacitor and method for reducing the impedance and length of a return-signal path

Abstract

The invention includes a device and method providing a return-signal pathway through a circuit board connector. In one embodiment of the invention, a circuit board connector having an integral bypass capacitor provides a return-signal path between the circuit boards without using the ground planes of the circuit boards outside of an area occupied by the connector. The circuit board connector includes first connector reference conductor arranged for coupling with a first circuit-board reference plane, a second connector reference conductor arranged for coupling with a second circuit-board reference plane, and a capacitor coupled between the first and second reference planes.

What is claimed is: 
     
       1. An electrical connector, comprising:
 a housing portion; 
 a first connector reference conductor coupled to the housing portion and arranged for coupling with a first conductive reference plane disposed outside of the housing portion and within a first circuit board; 
 a second connector reference conductor disposed in the housing portion and arranged for coupling with a second conductive reference plane disposed outside of the housing portion and within a second circuit board; and 
 a capacitor disposed in the housing portion and electrically coupling the first and second connector reference conductors. 
 
     
     
       2. The connector of  claim 1 , wherein the first connector reference conductor includes a contact arranged for coupling with the first conductive reference plane. 
     
     
       3. The connector of  claim 2 , wherein the first connector reference conductor further includes another contact arranged for coupling with a third conductive reference plane. 
     
     
       4. The connector of  claim 1 , wherein the second connector reference conductor includes a second contact arranged for coupling with the second conductive reference plane. 
     
     
       5. The connector of  claim 1 , wherein the connector is arranged for mounting on a circuit board. 
     
     
       6. The connector of  claim 1 , wherein at least one conductive reference plane is a power-supply plane. 
     
     
       7. The connector of  claim 1 , wherein one conductive reference plane is a ground plane. 
     
     
       8. An electrical connector, comprising:
 a first connector reference conductor arranged for coupling with a first conductive reference plane; 
 a second connector reference conductor arranged for coupling with a second conductive reference plane; and 
 a capacitor coupled between the first and second connector reference conductors, wherein the first conductive reference plane is a plane in a first circuit board and the second conductive reference plane is a plane in a second circuit board. 
 
     
     
       9. An electrical connector, comprising:
 a first connector reference conductor arranged for coupling with a first circuit-board reference plane; 
 a second connector reference conductor arranged for coupling with a second circuit-board reference plane; and 
 a capacitor coupled between the first and second connector reference conductors, wherein the first connector reference conductor is further arranged for coupling with a third circuit-board reference plane. 
 
     
     
       10. An electrical connector, comprising:
 a first connector reference conductor arranged for coupling with a first circuit-board reference plane; 
 a second connector reference conductor arranged for coupling with a second circuit-board reference plane; and 
 a capacitor coupled between the first and second connector reference conductors, wherein the first connector reference conductor is further arranged for coupling with a third circuit-board reference plane, and wherein the first connector reference conductor is a plane of a first circuit board and the third circuit-board reference plane is a plane of a second circuit board. 
 
     
     
       11. An electrical connector, comprising:
 a first connector reference conductor arranged for coupling with a first conductive reference plane of a first circuit board; 
 a second connector reference conductor arranged for coupling with a second conductive reference plane of a second circuit board; and 
 a capacitor coupled between the first and second connector reference conductors, wherein the first and second conductive reference planes are planes other than a ground plane. 
 
     
     
       12. An electrical connector, comprising:
 a first connector reference conductor arranged for coupling with a first conductive reference plane of a first circuit board; 
 a second connector reference conductor arranged for coupling with a second conductive reference plane of a second circuit board; and 
 a capacitor coupled between the first and second connector reference conductors, wherein the capacitor is coupled to the first connector reference conductor at a plurality of locations. 
 
     
     
       13. An electrical connector, comprising;
 a housing portion; 
 a first connector reference plane coupled to the housing portion and coupleable with a first conductive reference plane of a first circuit board disposed outside of the housing portion; and 
 a second connector reference plane disposed in the housing portion and coupleable with a second conductive reference plane of a second circuit board disposed outside of the housing portion, 
 the first and second connector reference planes being electrically coupled together inside of the housing portion, wherein the connector further includes a capacitor, and the first and second connector reference planes are coupled together by the capacitor. 
 
     
     
       14. An electrical system comprising:
 a first circuit board having a first reference plane and a first ground plane; 
 a second circuit board having a second reference plane and second ground plane; and 
 a connector that connects the first circuit board and the second circuit board, and that has a first capacitor coupling the first and second reference planes, wherein the connector further includes a second capacitor, and further wherein the first capacitor connects the first reference plane to the first ground and the second capacitor connects the second reference plane to the second ground plane. 
 
     
     
       15. A method of transmitting a return signal between a first circuit board and a second circuit board, comprising the steps of:
 transmitting a return signal in a first conductive reference plane of the first circuit board to a first connector reference conductor of an electrical connector; 
 capacitively coupling the return signal between the first connector reference conductor and a second connector reference conductor of the electrical connector; and 
 transmitting the return signal from the second connector reference conductor to a second conductive reference plane of the second circuit board. 
 
     
     
       16. An electrical connector, comprising:
 a housing means; 
 first means, coupled to the housing means, for coupling with a first conductive reference plane disposed outside of the housing means and within a first circuit board; 
 second means, disposed in the housing means, for coupling with a second conductive reference plane disposed outside of the housing means and within a second circuit board; and 
 means, disposed in the housing means, for capacitively coupling the first and second means. 
 
     
     
       17. An electrical connector, comprising:
 a housing portion; 
 a first connector reference conductor coupled to the housing portion and arranged for coupling with a first circuit-board reference plane disposed outside of the housing portion and within a circuit board; 
 a second connector reference conductor having a window and disposed in the housing portion and arranged for coupling with a second circuit-board reference plane disposed outside of the housing portion and within the circuit board; 
 an insulator disposed between the first and second connector reference conductors; and 
 a capacitor disposed in the housing portion and electrically coupling the first and second connector reference conductors through the window. 
 
     
     
       18. An electrical connector, comprising:
 a housing portion; 
 a first connector reference conductor coupled to the housing portion and arranged for coupling with a first circuit-board reference plane disposed outside of the housing portion and within a first circuit board; 
 a second connector reference conductor having a window and disposed in the housing portion and arranged for coupling with a second circuit-board reference plane disposed outside of the housing portion and within a second circuit board; 
 an insulator disposed between the first and second connector reference conductors; and 
 a capacitor disposed in the housing portion and electrically coupling the first and second connector reference conductors through the window.